Suspended solids separation systems and methods

ABSTRACT

A method that includes clarifying a thin stillage product in a mechanical processor to produce a fine suspended solids stream and a clarified thin stillage is provided. The method further includes providing the thin stillage product and the clarified thin stillage, separately or in a combined stream, to one or more evaporators to produce one or more reduced suspended solids streams, each stream having a reduced amount of suspended solids and a lower viscosity as compared to process streams having a comparable total solids content but containing a higher amount of suspended solids. The method can further included further processing of one or more of the reduced suspended solids streams to produce a bio-oil product.

This application claims the benefit of priority of U.S. ProvisionalApplication Ser. No. 61/501,030, filed Jun. 24, 2011, which isincorporated herein by reference in its entirety. This application is acontinuation of Canadian Application No. ______, filed on Jun. 21, 2012,and entitled “SUSPENDED SOLIDS SEPARATION SYSTEMS AND METHODS” and ofInternational Application PCT/US2012/043604, filed on Jun. 21, 2012, andentitled “SUSPENDED SOLIDS SEPARATION SYSTEMS AND METHODS”, both ofwhich claim benefit of U.S. Provisional Application Ser. No. 61/501,030,filed Jun. 24, 2011, all of which are hereby incorporated herein byreference in their entireties. This application is also a continuationof U.S. patent application Ser. No. 13/292,266, entitled “BIO-OILRECOVERY SYSTEMS,” filed on Nov. 9, 2011, which application is adivisional of U.S. patent application Ser. No. 13/105,789, filed on May11, 2011, entitled “BIO-OIL RECOVERY METHODS,” now issued as U.S. Pat.No. 8,192,627 (hereinafter “627 patent”), which application claimsbenefit under 35 U.S.C. 119 (e) of U.S. Provisional Application Ser. No.61/371,568 filed on Aug. 6, 2010, U.S. Provisional Application Ser. No.61/420,674 filed on Dec. 7, 2010, and U.S. Provisional Application Ser.No. 61/472,549, filed on Apr. 6, 2011, all of which are herebyincorporated by reference herein in their entireties.

BACKGROUND

The methods for producing various types of alcohol from grain generallyfollow similar procedures, depending on whether the grain millingprocess is operated wet or dry. One alcohol of great interest today isethanol, which can be produced from virtually any type of grain, but ismost often made from corn. Ethanol can also be made from variouscellulosic sources. Ethanol production generates co-products which canbe used as is or which can be further processed.

SUMMARY

There is a need for improving production processes for variousbio-products, such as alcohol production co-products. By removingsuspended solids in a thin stillage stream as described herein, not onlyare the total solids reduced in downstream process streams, theviscosity of these streams is also reduced, allowing for more efficientdewatering. Additionally and surprisingly, with the suspended solidsremoved, soluble solids are now easier to concentrate. As a result,water can be removed in a more efficient manner, thus reducing operatingcosts, such as natural gas costs for dryers.

The various embodiments described herein not only allow various reducedsuspended solids streams, such as a molasses product, to be produced,but also provide for enhanced recovery of bio-oil from alcoholproduction co-products. A solids product with enhanced amounts offermentation aids can also be produced.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are illustrated by way of example and not limitation inthe figures of the accompanying drawings in which:

FIG. 1A is a schematic illustration of a conventional stillageprocessing system;

FIG. 1B is a schematic illustration of a bio-oil recovery system;

FIG. 2 is a schematic illustration of a suspended solids separationsystem in combination with a bio-oil recovery system capable ofproducing an emulsion concentrate according to various embodiments;

FIG. 3 is a schematic illustration of a mechanical processor forseparating suspended solids according to various embodiments;

FIG. 4 is a schematic illustration of a suspended solids separationsystem in combination with a bio-oil recovery system according tovarious embodiments;

FIG. 5 is a schematic illustration of a suspended solids separationsystem without a bio-oil recovery system according to variousembodiments;

FIG. 6 is an image of test vials showing suspended solids captureefficiency for a high-speed centrifuge according to various embodiments;

FIG. 7 is an image of spin vials showing suspended capture efficiencyfor a high-speed centrifuge according to various embodiments;

FIG. 8 is a graph showing fraction emulsion versus degree Brix (i.e.,sugar content) concentration in clarified concentrated thin stillageaccording to various embodiments; and

FIG. 9 is an image of spin vials containing a molasses product accordingto various embodiments.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, embodiments are described insufficient detail to enable those skilled in the art to practice them,and it is to be understood that other embodiments may be utilized andthat chemical and procedural changes may be made without departing fromthe spirit and scope of the present subject matter. The followingdetailed description is, therefore, not to be taken in a limiting sense,and the scope of embodiments of the present invention is defined only bythe appended claims.

The various embodiments provide suspended solids separation systems andmethods related thereto. Although the systems and methods describedherein focus primarily on separating suspended solids from thin stillageresulting from ethanol production, any of the systems and methodsdescribed herein can be used to separate suspended solids from othertypes of bio-product process streams, including, for example, variousother alcohol streams, such as butanol (e.g., isobutanol), biochemicalstreams, and the like.

The term “biomass” as used herein, refers generally to organic matterharvested (in particular seeds such as corn kernels or wheat kernels) orcollected from a renewable biological resource as a source of energy.The renewable biological resource can include plant materials (e.g.,plant biomass), animal materials, and/or materials producedbiologically. The term “biomass” is not considered to includenon-renewable fossil fuels, such as coal, petroleum and natural gas.These types of fossil fuels are formed by natural processes (such asanaerobic decomposition of long dead, buried organisms) and containhydrocarbons such as alkanes, cycloalkanes, and various aromatichydrocarbons, but do not normally include glycerides (e.g., tri-, di-,mono-).

The terms “plant biomass” or “ligno-cellulosic biomass” as used herein,are intended to refer to virtually any plant-derived organic matter(woody or non-woody) available to produce energy on a sustainable basis.Plant biomass can include, but is not limited to, agricultural cropwastes and residues such as corn stover, wheat straw, rice straw, sugarcane, bagasse, and the like. Plant biomass can further includebyproducts of plant biomass, such as molasses. Plant biomass furtherincludes, but is not limited to, woody energy crops, wood wastes andresidues such as trees, which can include fruit trees, such asfruit-bearing trees, (e.g., apple trees, orange trees, and the like),softwood forest thinnings, barky wastes, sawdust, paper and pulpindustry waste streams, wood fiber, and the like. The skins and/or rindsof the various fruits can also be used as plant biomass. Holo-cellulosicmaterials (hemicellulose and cellulose polymers) found in grain seeds,particularly those concentrated in the pericarp or hull of the seed, butoften found in lower concentrations throughout the seed can also be usedas plant biomass.

Additionally grass crops, such as various prairie grasses, includingprairie cord grass, switchgrass, big bluestem, little bluestem, sideoats grama, energy sorghum and the like, have the potential to beproduced large-scale as additional plant biomass sources. For urbanareas, potential plant biomass includes yard waste (e.g., grassclippings, leaves, tree clippings, brush, etc.) and vegetable processingwaste. Plant biomass is known to be the most prevalent form ofcarbohydrate available in nature.

The term “low water extractable non-starch polysaccharide-containingplant biomass” or “low NSP plant biomass,” as used herein, refers toplant biomass containing less than about 0.5%, by weight, down to 0%NSP. Corn, in particular the corn kernel, is one example of a low NSPplant biomass.

The term “biofuel” as used herein, refers to any renewable solid, liquidor gaseous fuel produced biologically, such as bio-oils, including forexample, bio-oils derived from biomass. Most biofuels are originallyderived from biological processes such as the photosynthesis process andcan therefore be considered a solar or chemical energy source. Biofuelscan be derived from biomass synthesized during photosynthesis, such aswith agricultural biofuels (defined below). Other biofuels includealgaculture biofuels (from algae), municipal waste biofuels (residentialand light commercial garbage or refuse, with most of the recyclablematerials such as glass and metal removed) and forestry biofuels (e.g.,trees, waste or byproduct streams from wood products, wood fiber, pulpand paper industries). Biofuels also include, but are not limited to,biodiesels, bioethanol (i.e., ethanol), biogasoline, biomethanol,biobutanol, biogas, and the like.

The term “bio-oil” as used herein, refers to food-grade and non-foodgrade oils and fats that are derived from plants and/or animals (e.g.,vegetable oils and animal fats, which contain primarily triglycerides,but can also contain fatty acids, diglycerides, and monoglycerides. (Asused herein, the term “fat” is understood to include “lipids”). Examplesof bio-oils derived from plants include, but are not limited to, cornoil, flaxseed oil, canola oil, and the like. See also the listing ofbiofuel sources noted in the definition for “agricultural biofuel”below, which are also useful as sources for bio-oil.

The term “agricultural biofuel” as used herein refers to a biofuelderived from agricultural crop (e.g., grains, such as corn and soybeans)plant biomass, crop residues, grain processing facility wastes (e.g.,wheat/oat hulls, corn/bean fines, out-of-specification agricultural orbiomass materials, etc.), livestock production facility waste (e.g.,manure, carcasses, etc.), livestock processing facility waste (e.g.,undesirable parts, cleansing streams, contaminated materials, etc.),food processing facility waste (e.g., separated waste streams such asgrease, fat, stems, shells, intermediate process residue,rinsing/cleansing streams, etc.), value-added agricultural facilityco-products (e.g., distiller's grain of any moisture content and/orsyrup from ethanol production facilities, etc.), and the like. Examplesof livestock include, but are not limited to, cattle, hogs, turkey, fishor chicken. Examples of agricultural crops include, but are not limitedto, any type of non-woody plant (e.g., cotton), grains, including anytype of cereal grains such as corn, wheat, soybeans, sorghum, barley,oats, rye, milo, rape seeds, canola, sunflower, pennycress, and thelike, herbs (e.g., peanuts), herbaceous crops such as switchgrass,alfalfa, other starch containing crops such as bagasse, sugarcane, andother bio-oil-bearing starch or sugar based materials, and so forth.Ethanol and biodiesel are examples of agricultural biofuels.

The term “stillage” as used herein refers to a co-product producedduring production of a biofuel, and is sometimes referred to as “slop.”When used without qualification, the term “stillage” can refer to wholestillage, thin stillage, or concentrated stillage (such as condenseddistillers soluble, i.e., syrup, which can be produced from biofuelprocess streams, e.g., ethanol production process streams). Such streamscontain soluble organic and inorganic compounds, suspended materialscontaining protein, carbohydrate, and bio-oil fractions and may have afree bio-oil component and an emulsified bio-oil component, or all ofthe bio-oil may be emulsified.

The term “free oil” or “free bio-oil” as used herein, refers to abio-oil that is not emulsified, physically or chemically bound ortrapped by components in the process stream and can be phase separatedfrom the process stream, i.e., recovered from the process stream viamechanical processing and/or non-mechanical processing as definedherein.

The terms “emulsion” or “emulsified layer” as used herein refer to amixture of two or more immiscible (unblendable) liquids, i.e., liquidsthat are sparingly soluble within each other. Emulsions are part of amore general class of two-phase systems of matter called colloids.Although the terms colloid and emulsion are sometimes usedinterchangeably, emulsion tends to imply that both the dispersed and thecontinuous phase are liquid. In an emulsion, one liquid (the dispersedphase) is dispersed in the other (the continuous phase) (Wikipediahttp://en.wikipedia.org/wiki/Emulsion). Whether an emulsion becomes awater-in-oil emulsion or an oil-in-water emulsion depends on the volumefraction of both phases and on the type of emulsifier.

Generally, the Bancroft rule applies, which suggests that emulsifiersand emulsifying particles tend to promote dispersion of the phase intowhich they are not well dissolved; for example, proteins dissolve betterin water than in oil. As a result, proteins tend to form oil-in-wateremulsions, i.e., proteins promote the dispersion of oil dropletsthroughout a continuous phase of water.

An emulsion can contain entrapped components, such as bio-oil, as wellas other components, including, but not limited to, starches, free fattyacids (FFA) (e.g., arachidic acid, stearic acid, palmitic acid, erucicacid, oleic acid, arachidonic acid, linoleic acid and/or linolenicacid), fatty acid lower(alkyl) esters, phospholipids, grain germfractions, yeast, protein, fiber, glycerol, residual sugars, otherorganic compounds and/or other inorganic compounds such as anion andcation salts of organic acids (e.g., metallic salts such as sodiumsulfate, sodium sulfite, magnesium sulfate and potassium phytate,magnesium phytate, magnesium phosphate, sodium carbonate, magnesiumoxalate, calcium oxalate, caratenoids, and/or antioxidants).

The term “emulsion concentrate” as used herein refers to a stableemulsion (water-in-bio-oil or bio-oil-in-water) containing minor amountsof other components from a processing stream, such as from theprocessing streams described herein.

The term “mechanical processing” or “mechanical process” as used hereinrefers to interaction of a machine or device with any portion of aprocess stream sufficient to cause or alter motion of the processstream. Mechanical processing is accomplished with mechanical forceand/or addition and/or reduction of kinetic energy.

The term “mechanical processor” or device as used herein refers to amachine or device (with or without moving parts) capable of carrying outmechanical processing and can further include a device capable ofcarrying out mechanical processing in combination with non-mechanicalprocessing (such as the use of a centrifuge to add centripetal force toaid phase separation caused by gravity).

The term “non-mechanical processing” or “non-mechanical process” as usedherein refers to a non-mechanical process that causes change in aprocess stream other than by imparting and/or altering motion of theprocessing stream. A non-mechanical process includes any type ofchemical process such as gravity separation.

The term “non-mechanical processor” as used herein refers to a machineor device capable of carrying out non-mechanical processing on a processstream. One example of a non-mechanical processor is a gravity-settlingtank.

The term “chemical processing” or “chemical process” as used hereinrefers to a process that changes the composition of the process streamin one or more steps with or without the use of added components andwith or without added (or reduced) heat and/or added or reducedpressure. A chemical reaction is one type of chemical process. Oneexample of such a reaction is the emulsion breaking reaction asdescribed in the '627 patent. Other examples of a chemical processinclude catalysis, coagulation, and flocculation. A chemical process canalso refer to a passive chemical process.

The term “passive chemical processing” or “passive chemical process” asused herein refers to a process that allows a chemical change to occurnaturally in a process stream over time without adding additionalcomponents to the process stream and/or heating and/or pressurizing theprocess stream. Gravity separation of phases in a process stream is oneexample of a passive chemical process as it uses only the force ofgravity to allow separation to occur.

The term “aqueous phase” as used herein refers to a process streamcontaining primarily water and solids,—and which can further containglycerin, acetic acid, sulfuric acid, residual soluble sugars, solubleproteins, and trace minerals, such as Mg, Fe, and Ca. In the systemdescribed in the '789 application, the aqueous phase further includes anamount of emulsion breaking additive (as defined therein).

The term “bio-oil phase” as used herein refers to a process streamcontaining primarily bio-oil, and which can further contain an amount ofemulsion breaking additive and other minor components.

The term “evaporation” as used herein refers to removal or vaporizationof a solvent. Use of increased temperature and/or decreased pressure isone type of evaporation that is often referred to as “flashing” or“flash evaporation.”

The term “total solids” as used herein refers to all components in aprocess stream other than water. When used without qualification, theterm “solids” is intended to refer to total solids, by weight.

The term “dissolved solids” or “solubles” as used herein refers to solidparticles that are mixed sufficiently with the fluid in a process steamsuch that they do not separate from the process stream during mechanicalprocessing.

The term “fine suspended solids stream” as used herein refers to aprocess stream containing suspended solid particles, i.e., “insolubles,”which can be separated from the process stream. The particles in thefine suspended solids stream are primarily less than about 20micrometers in diameter, but can also include larger solid particles.

The term “thin stillage” as used herein refers to a conventional processstream produced as a co-product of alcohol production (e.g., ethanolproduction) which contains between about 3% and about 15%, by weight, oftotal solids, of which about 25% to 75% are suspended solid particles.

The term “concentrated thin stillage” or “syrup” as used herein refersto a conventional process stream produced as a co-product of alcoholproduction (e.g., ethanol production) which contains between more thanabout 20% up to about 45%, by weight, of solids, of which about 25% to75% are suspended solid particles.

The term “clarified thin stillage” as used herein refers to a processstream containing between about 3% and about 15%, by weight, of totalsolids, of which less than 25% are suspended solid particles. Aclarified thin stillage stream typically has a cloudy appearance.

The term “thin stillage product” as used herein refers to a processsteam containing various ratios of thin stillage and clarified thinstillage. At start-up, the thin stillage product can comprise only thinstillage.

The term “clarified concentrated thin stillage” as used herein refers toa process stream containing between about 15% and 40%, by weight, oftotal solids, of which less than about 25% are suspended solidparticles. A clarified concentrated thin stillage stream typically has acloudy appearance.

The term “molasses product” as used herein refers to a process streamcontaining at least 45% by weight of total solids, of which less than25% are suspended solid particles. As such, the “molasses product”described herein can be used as a substitute for conventional“molasses”, which is a viscous by-product from the processing of sugarcane, grapes or sugar beets into sugar.

The term “reduced suspended solids stream” as used herein refers to aprocess stream having any total solids content between about 2% up tosubstantially or about 100%, by weight, but which has a reduced amountof suspended solids particles as compared to conventional processstreams with comparable total solids content, and can further include astream containing no suspended solid particles. Process streamscomprised of clarified thin stillage, thin stillage product (afterstart-up), clarified concentrated thin stillage, and molasses productsare examples of reduced suspended solids streams. Such process streamshave a lower viscosity as compared to conventional process streams withcomparable total solids content as these conventional streams containmore suspended solid particles.

Grain-based ethanol can be produced from a wet mill process, a dry grindethanol process, or a “modified” dry grind ethanol process as isunderstood in the art. See, for example, Kohl, S., Ethanol 101: Overviewof Ethanol Production, Ethanol Today, July 2003, pp. 36-37 for adetailed description of a typical dry grind ethanol process, which ishereby incorporated herein by reference in its entirety. See also patent'627 and the various Kohl references cited herein for additional detailson dry grind and modified dry grind processes as on typical wet millingprocesses.

Regardless of the specific process used (wet mill, dry grind or modifieddry grind), conventional ethanol production results in usefulco-products which, after mechanical processing, or heating andmechanical processing, are designed to recover free bio-oil and/orbio-oil present in an unstable emulsion. (See also the '627 patent inwhich bio-oil is recovered from a stable emulsion).

Co-products produced as a result of distillation and dehydration includewhole stillage, which is typically subject to a centrifugation ordecanter step to separate insoluble solids (“wet cake”) from the liquid(which is oftentimes referred to as “centrate” until it enters astillage tank, if present, at which point it is sometimes referred to as“thin stillage”). In a dry grind ethanol process, stillage entersevaporators in order to boil away moisture, producing a concentratedsyrup containing the soluble (dissolved) solids from the fermentation.See, for example, Kohl, S., Ethanol 101-9: Evaporation, Ethanol Today,May 2004, pp 36-39, which is herein incorporated by reference in itsentirety.

This concentrated syrup can be mixed with the centrifuged wet cake, andthe mixture sold to beef and dairy feedlots as Distillers Wet Grain withSolubles (DWGS). Alternatively, the wet cake and concentrated syrupmixture may be dried and sold as Distillers Dried Grain with Solubles(DDGS) to dairy and beef feedlots. See, for example, Kohl, S., Ethanol101-10: Drying-Production of DDGS, Ethanol Today, June 2004, pp. 34-36,which is hereby incorporated herein by reference in its entirety.

Adding syrup to wet cake has limited economic value. Additionally, usingsyrup to produce DDGS is expensive, since the dryers utilize a largeamount of energy to evaporate water from the syrup. Additionally, syrupcan contain sulfur and salts, both of which can lower the quality, andthus the selling price, of the DDGS. With its lower protein content,syrup can also dilute the protein content of the DDGS. The appearance ofthe DDGS can also be affected by addition of syrup, giving it anundesirable brown color.

Selling syrup as a liquid feed supplement can be about 3 to 6 times lesscost effective than selling DDGS. Syrup has a low value for a number ofreasons, such as wide variability of composition, poor handlingcharacteristics, high water content (greater than 60% by weight) andhigh viscosity (semi-solid) upon cooling such that it requires heatingin order to be pumped.

In contrast, in the various embodiments described herein, at least aportion of a thin stillage product is provided to a mechanical processorto separate suspended solids (primarily fine suspended solids having adiameter less than about 20 micrometers) present in the process streamfrom the dissolved solids also present in the process stream to producea fine suspended solids stream

In some embodiments, the fine suspended solids stream can then be addedto the wet cake product fraction, resulting in DDGS having increasedvalue due to the presence of high value components, such as single cellproteins, e.g., yeast (See, for example, FIG. 5). As a result, the dryerload (e.g., 119) can be reduced, which not only reduces costs for thedryer operation, but can also allow the entire facility to run moreefficiently. It is also likely that the DDGS provided is of higherquality due to use of lower dryer temperatures.

In the various embodiments described herein, a thin stillage productfrom an alcohol production facility is provided to a mechanicalprocessor to separate it into a fine suspended solids stream andclarified thin stillage. Some or all of the clarified thin stillage isthen returned to the thin stillage product. By clarifying at least aportion of the thin stillage and then providing the two products, eitherseparately or in a combined stream, to one or more evaporators, it isnow possible to produce a stream having a reduced suspended solidscontent, i.e., a reduced suspended solids stream. Examples of a reducedsuspended solids stream include, for example, a molasses product havinga total solids content no less than about 45% by weight, with asuspended solids content of less than 25% down to substantially or about0%. In one embodiment, the fine suspended solids stream containsfermentation aids (e.g., single cell proteins such as yeast), which canbe dried and sold. In one embodiment, use of the solids separationtechnology in combination with bio-oil recovery systems improves bio-oilyield.

Conventional attempts to remove suspended solids from process streamsinclude operations that separate whole stillage to produce an insolublesolids portion containing non-single celled high protein grain productssuch as corn meal. In contrast to thin stillage, whole stillage is knownto contain large fiber and protein particles with a substantial portion,i.e., at least 30 up to 80% of these particles greater than 20micrometers in diameter.

Other attempts to separate stillage include various non-mechanicaland/or chemical separation techniques. Such techniques are known toresult in limited suspended solids recovery.

Other attempts to remove fine suspended particles have includedelectrostatic or ionic precipitation, which are known to achieve lessthan satisfactory results. Yet other attempts include pH adjustment tocause precipitation. However, costs of adjusting pH can be quite high.Additionally, higher pH products can become discolored, thus reducingtheir value. Additional problems with pH adjustment include theproduction of soap, and reduced palatability for animals consuminganimal feed made from these products.

FIG. 1A shows a prior art system 100A for processing stillage from anethanol production process. Stillage can be subjected to dewatering by avariety of means, such as by evaporation or pressing before or insteadof providing to a drying zone. In FIG. 1, whole stillage 124 (fromethanol production) is provided to a decanter 126 where it is separatedinto wet cake 128 and centrate 127. A portion of the centrate 127 can berecycled as “backset” in the ethanol production facility and theremaining portion, although also having the identical content ascentrate 127, is commonly referred to as “thin stillage” at this pointin the process. The thin stillage 102 is then provided to evaporators104 for concentration.

As shown in FIG. 1A, the resulting concentrated thin stillage (i.e.,syrup) 106 exiting the evaporators 104 is provided to a syrup tank 118.The concentrated thin stillage 106 can be dried in a dryer 119 (oftenreferred to as a “Distiller's Grain Dryer”) to produce DDGS as discussedabove and/or sold as is and/or further processed. Alternatively oradditionally, a portion of the concentrated thin stillage 106 can becombined with the wet cake 128 and the mixture sold as DWGS and/or themixture can be provided to the dryer 119 to produce DDGS. The wet cake128 exiting the decanter 126 can alternatively be provided as is to thedryer 119.

FIG. 1B shows a bio-oil recovery system 100B for processing stillagefrom an ethanol production process, as described in the '627 patent,which includes all of the steps as described in FIG. 1A, together withsteps directed to producing free bio-oil. As shown in FIG. 1B,concentrated thin stillage 106 is provided to a centrifuge 112 forfurther separation into free bio-oil 113, de-oiled concentrated thinstillage 114, and solids 115. The free bio-oil 113 is provided tobio-oil storage 116. The de-oiled concentrated thin stillage 114 canthen be returned to the evaporators 104 as shown, and/or can be providedto the process stream exiting the evaporators 104 which containsconcentrated thin stillage (i.e., syrup) 106 and/or directly to thesyrup tank 118.

In contrast, the novel embodiments described herein do not provide allof the thin stillage 102 directly to the evaporators 104 as shown inFIGS. 1A and 1B. Instead, a thin stillage product 260 containing areduced amount of suspended solids is provided to an evaporator 204 asshown in the suspended solids separating system 200 in FIG. 2. The thinstillage product 260 (comprised at start-up of thin stillage 202 and,during operation, of thin stillage 202 in combination with clarifiedthin stillage 242) can be provided to a mechanical processor 240.

In the embodiment shown in FIG. 2, the thin stillage product 260 isoptionally held in a thin stillage product tank 203 for a suitableperiod of time prior to being provided to the mechanical processor 240.Use of a holding tank such as the thin stillage product tank 203 in thismanner can serve as a system control device by providing a quantity ofthin stillage product 260 for use in this portion of the system, whetheror not the processes upstream are operating or down for repair. The thinstillage product tank 203 can, optionally, utilize a heat source, suchas steam from an in-house source, to increase the temperature of thethin stillage product 260 if desired. In other embodiments, there is nothin stillage product tank 203 and the thin stillage product 260 isprovided directly to the mechanical processor 240. In one embodiment,only a portion of the thin stillage product 260 is provided to themechanical processor 240, with the remainder provided directly to theevaporator 204.

In the embodiment shown in FIG. 2, the suspended solids separatingsystem 200 includes a bio-oil recovery system 250 (as described in, forexample, patent '627). In this embodiment, whole stillage 124 is derivedfrom an ethanol production facility. In other embodiments, the wholestillage 124 can be derived from any type of alcohol productionfacility, such as an ethanol or butanol production facility. The system200 shown in FIG. 2 includes separating whole stillage 124 in a decanter126 to produce centrate 227 and a wet cake product 228, which, atstart-up comprises conventional wet cake, and thereafter, can comprise amolasses product-containing wet cake, and, in some embodiments, canadditionally or alternatively include fine suspended solids from a finesuspended solids stream (e.g., 529, FIG. 5).

In the embodiment shown in FIG. 2, the wet cake product 228 is providedto a first dryer 219 to produce DDG 220. A portion of the centrate 227is provided as “backset,” a portion or all of which can be provided tothe mechanical processor 240 as shown in FIG. 2. The other portion ofthe centrate 227, although compositionally the same, is referred to inthis point of the process as thin stillage 202.

In one embodiment (not shown), all of the centrate 227 is insteadprovided to the mechanical processor 240. In this embodiment, theclarified thin stillage 242 can be split into more than one stream, suchthat a portion of it becomes backset and a portion is provided to theevaporator 204.

As noted above, the thin stillage product 260 enters the mechanicalprocessor 240 where it is separated into a fine suspended solids stream229 and clarified thin stillage 242. The clarified thin stillage 242(now depleted in protein and enriched in bio-oil and soluble as comparedto the thin stillage product 260) can be returned to the thin stillageproduct tank 203. Thereafter, the thin stillage product 260 is providedto the evaporator 204 for dewatering.

At this point in the process, the thin stillage product 260 is comprisedof a mixture of thin stillage 202 and clarified thin stillage 242, withthe ratios of each varying throughout the operation. The thin stillageproduct 260 has a reduced suspended solids content as compared to thethin stillage 202. In one embodiment, a portion of the clarified thinstillage 242 is provided directly to the evaporator 204.

The fine suspended solids stream 229 can be processed in any suitablemanner. In the embodiment shown in FIG. 2, the fine suspended solidsstream 229 is provided to a second dryer 244 to produce Dry Distiller'sSolubles (DDS) 246. The second dryer 244 is, in one embodiment, anydryer capable of handling a highly viscous material (i.e., having aviscosity greater than about 5000 centipoise), such as a non-rotarydryer, (e.g., steam tube dryer, flash dryer, ring dryer, spray dryer,tunnel dryer and the like). In other embodiments, as shown in FIG. 5,for example, a portion or all of the fine suspended solids stream 229can be provided to the decanter 126 to produce the wet cake product 228.In yet another embodiment, prior to entering the second dryer 244, thefine suspended solids stream 229 is subjected to a dewatering step toremove additional water prior to drying. The dewatering can include anysuitable means, including, but not limited to, centrifuging (e.g.,high-G compactor centrifuge, e.g., 370 in FIG. 3), filtering, decanting,and the like.

The DDS 246 contains an increased amount of single cell proteins, e.g.,yeast, as well as a reduced amount of grain protein, fiber, and bio-oil.In one embodiment, the DDS 246 is a high protein, low fiber feed product(e.g., at least about 30% protein and no more than about 10% fiber, byweight). In one embodiment, single cell proteins are present in the finesuspended solids stream 229 at a level below 40%, by weight. In oneembodiment single cell proteins are present at a level greater than 40%,by weight, such as up to greater than 70% or 90%, including any valuesthere between.

Referring again to FIG. 2, the evaporator 204 can represent multipleeffect evaporators, such as any number of evaporators, such as one, two,three or more, such as four, five, six, or seven evaporators, furtherincluding, for example, eight (8) evaporators. In some embodiments, morethan eight evaporators may be used. In such embodiments, forward feedingcan take place when the thin stillage product 260 enters the evaporator204 through a first effect evaporator that is run at the highesttemperature. The thin stillage product 260 is then partiallyconcentrated, as some of the water has vaporized and can be useddownstream. This clarified and partially concentrated product (notshown) are then fed into a second effect evaporator that is slightlylower in temperature than the first effect evaporator. The second effectevaporator uses the heated vapor created from the first stage as itssource of heating. In one embodiment, the evaporator 204 comprises firsteffect and second effect evaporators that utilize recycled steam.

In one embodiment, the first effect evaporators use steam from a boiler(not shown) in the alcohol production facility (e.g., ethanol productionfacility) to generate process steam. This steam becomes cooled and canbe re-used in a distillation step (not shown). In one embodiment, thesecond effect evaporators also use recycled steam. In one embodiment,direct steam from the boiler is used in the distillation step and theevaporator 204 comprises multiple evaporators which are run “postdistillation.”

In one embodiment, the evaporator is a multiple effect evaporator asdescribed above, such as a three effect evaporator. In one embodiment,the evaporator is a four effect evaporator. In one embodiment, theevaporator is a five effect evaporator. In one embodiment, theevaporator is a Mechanical Vapor Recompression (MVR)-type energy cascadesystem.

In embodiments having eight (8) evaporators, the first evaporator can berun at temperatures as high as about 210° F. (99° C.), with the fourthevaporator run at temperatures between about 200° F. (93° C.) and about205° F. (96° C.). In other embodiments with fewer evaporators or withone evaporator, the temperatures can vary between about 22° C. and about121° C., such as between about 130° F. (54.4° C.) and about 210° F. (99°C.), including any ranges there between.

As the thin stillage product 260 progresses through the evaporator 204,it becomes increasingly concentrated to the point it eventually becomesa molasses product 206, which, in one embodiment, can have a waterconcentration between about 5% and about 55%.

It is possible to withdraw the reduced suspended solids product at anypoint or points during evaporation, depending on the desired finalproduct or products. In one embodiment, a reduced suspended solidsproduct, such as clarified concentrated thin stillage 205 having a waterconcentration of between about 65% and about 75% by weight, such asabout 70%, is withdrawn from the evaporator 204 and provided to acentrifuge 212 to produce solids 215 and a clarified emulsionconcentrate 222. The clarified emulsion concentrate 222 is provided tothe bio-oil recovery system 250, which produces a bio-oil phase 236 andan aqueous phase 234. The bio-oil phase 236 is then provided to bio-oilstorage 216 where it can be sold into various markets, such as the feed,chemical and/or biofuel oil markets at a higher selling price thanconventional syrup or Distiller's Dry Grain Solubles (DDGS).

The resulting de-oiled reduced suspended solids product, i.e., thede-oiled clarified concentrated thin stillage 214, can be returned tothe evaporator 204 where the evaporation process continues until themolasses product 206 is produced. In one embodiment, the molassesproduct 206 is a cooled molasses product, which is a solid product thatis congealed. However, in order to move the molasses product 206 throughthe system 200, in most embodiments, the molasses product 206 is heatedsufficiently to allow it to be pumped. In one embodiment, the molassesproduct 206 is heated to a temperature of at least about 100° F. (38°C.). In this way, although highly concentrated, the molasses product 216is a pumpable liquid product due to the reduced amount of suspendedsolids.

In one embodiment, a reduced suspended solids stream, which is moreconcentrated than the thin stillage product 260, but less concentratedthan the molasses product 206 can be withdrawn from the evaporator (notshown in FIG. 2). Such a product can have a total solids content betweenabout 30% and 90%, by weight, with the suspended solids comprising lessthan about 25%, by weight, of the total solids content, is produced.

In one embodiment, the reduced suspended solids stream is the molassesproduct 206 having a total solids content greater than about 45%, byweight, such as greater than about 60% or 70% or 80% or 90% or 95% orhigher up to substantially 100%, as long as the molasses product 206 isstill pumpable at elevated temperatures, including any range therebetween.

In one embodiment, the suspended solids in the molasses product 206comprise less than 25%, by weight of the total solids, such as about 20%or about 0% or lower, down to about 5% or lower, down to about 1% orlower, such as about 0.001%, by weight, down to substantially or aboutzero %, including any range there between. In one embodiment, themolasses product 206 has a total solids content between about 65% and75%, by weight, such as about 70%, with a suspended solids contentcomprising less than 3.5%, by weight, of the total solids content.

It is possible to withdraw the clarified concentrated thin stillage 205and/or the molasses product 206 from the evaporator 204 at temperatureslower than their boiling points. In one embodiment, the clarifiedconcentrated thin stillage 205 and/or another reduced suspended solidsstream (not shown) and/or the molasses product 206 is withdrawn at atemperature of about 205° F. (96.1° C.) or below. In embodiments havingeight evaporators, the clarified concentrated thin stillage 205 and/oranother reduced suspended solids stream (not shown) and/or molassesproduct 206 may be withdrawn from any of the evaporators, such as fromthe fourth, fifth, sixth, seventh, and/or eighth evaporators attemperatures of between about 170° F. (76.7° C.) and about 205° F.(96.1° C.). The decision as to which evaporator 204 the clarifiedconcentrated thin stillage 205 and/or any other reduced suspended solidsprocess stream (not shown) and/or molasses product 206 should be removedfrom depends on several factors, including, but not limited to, thevolume % of unstable emulsion present, viscosity of the clarifiedconcentrated thin stillage 205 and/or other reduced suspended solidsprocess stream and/or molasses product 206, and the like, which can varydepending on upstream processing conditions.

Referring again to FIG. 2, the molasses product 206 exiting theevaporator 204 can be at any suitable pH. In one embodiment, themolasses product 206 is at a pH of between about 2 and about 5.8. In oneembodiment, the pH may be closer to pH 7. In one embodiment, the pH maybe higher, such as about 8.3.

By separating out the suspended solids in the fine suspended solidsstream 229, the thin stillage product 260 entering the evaporator 204now contains a reduced amount of suspended solids. As a result, it isnow possible to efficiently and economically produce clarifiedconcentrated thin stillage 205 and/or any other reduced suspended solidsprocess stream, including a molasses product 206 as a co-product ofalcohol production, e.g., ethanol production. These reduced suspendedsolids products, such as the molasses product 206 shown in FIG. 2, canthen be provided to a molasses product tank 218 and sold and/or combinedwith the wet cake product 228 and dried in the first dryer 219 toproduce DDGS 221. In one embodiment, the molasses product 206 isadditionally or alternatively combined with the wet cake product 228and—can optionally also be provided as DWGS.

The molasses product 206 further contains an amount of bio-oil that isgreater than the amount, per volume, of bio-oil present in conventionalconcentrated thin stillage. In one embodiment, the molasses product 206contains two to three times the amount of bio-oil, per volume, ascompared to conventional concentrated thin stillage.

As a comparison and for example purposes only, a given volume ofconcentrated thin stillage having about 35% total solids, by weight, cancontain about 4 to about 6% bio-oil, by volume, whereas the same volumeof molasses product 206 can have about 70% total solids, by weight, andcontain about 8 to about 12% bio-oil, by volume. As such, mechanicalprocessing, such as centrifugation, can run more efficiently as comparedwith mechanical processing performed in conventional operations. In oneembodiment, the number of centrifuges used in the system can be reduced,such as by one-half, such as from two to one.

In the embodiment shown in FIG. 2 the system further includes a bio-oilrecovery system 250, such as is described in the '627 patent. In thisembodiment, the operation of the centrifuge 212 is adjusted to dewateror concentrate the clarified concentrated thin stillage 205 to producean emulsion concentrate, which, since there is a reduced amount ofsuspended solids contained therein, is referred to in FIG. 2 as aclarified emulsion concentrate 222. The clarified emulsion concentrate222 is thereafter provided to an emulsion breaking/phase separatingprocess 250, which produces an aqueous phase 234 and a bio-oil phase236.

The mechanical processor 240 is capable of changing the nature of thesolid particles, i.e., neutralizing the electrostatic charge of finesuspended solids from dissolved solids in the process stream, thusallowing the fine suspended solids to bind together. In this way, thefine suspended solids can be separated from the thin stillage product260. The mechanical processor 240 can comprise any suitable devicecapable of separating the fine suspended solids mixture 229 asdescribed.

Separation efficiency of the mechanical processor 240, i.e., the abilityof the mechanical processor 240 to separate suspended solids from theprocess stream, is also a consideration. In one embodiment, theseparation efficiency is at least 50%, up to about 60%, 70%, 80%, 90% orhigher, including any ranges there between. In one embodiment, theseparation efficiency is at least 80%. In one embodiment, the separationefficiency is between about 80% and about 90% or between about 85% andabout 95%. In one embodiment, the separation efficiency is at least 96%,such as about 96.7%. Higher separation efficiencies may also bepossible.

In one embodiment, the mechanical processor 240 is a centrifuge, such asa disc stack centrifuge. A disc stack centrifuge is avertically-oriented centrifuge with the capability to separate finesuspended particles from solution more effectively than a standardcentrifuge. The enhanced separation efficiency is due to the higherG-force produced by the disc stack unit as well as the large surfacearea provided by the discs inside the centrifuge. The discs are stackedclosely together to provide additional surface area for more effectiveseparation. As the centrifuge spins, centrifugal force sends the densersolids outward against the wall of the bowl, and the less dense liquidis forced to the center. The fine suspended solids stream 229 isdischarged through a fixed port or by rapidly opening and closing spacein the wall of the centrifuge, and the clarified thin stillage 242 isdischarged through a pipe at the top (not shown). In one embodiment, anysuitable filtration system comprising one or more filters, isadditionally or alternatively used as a mechanical processor 240. In oneembodiment, the system includes a bio-oil recovery system 250 and themechanical processor 204 comprises a filtration system.

In one embodiment, as shown in FIG. 3, the mechanical processor 240comprises both a disc stack centrifuge 360 and a high “G” compactingcentrifuge 370. The high “G” compacting centrifuge 370 is capable ofoperating in excess of 3000 G forces. In the embodiment shown in FIG. 3,the thin stillage product 260 enters the disc stack centrifuge 360,which separates the thin stillage product 260 into clarified thinstillage 242 and an intermediate fine suspended solids stream 365. Theintermediate fine suspended solids stream 365 is provided to the high“G” compacting centrifuge 370 which produces the fine suspended solidsstream 229 which is provided to the decanter (226, FIG. 2) or to thesecond dryer (244, FIG. 2). In one embodiment, the fine suspended solidsstream 229 has a water concentration of about 75% to about 80%, thoughlower water contents may be possible.

In the embodiment shown in FIG. 3, wash water 372 can be provided to thedisc stack centrifuge 360 to wash dissolved solids away from thesuspended solids material. In one embodiment, the wash water 372 isprovided within an internal loop. In one embodiment, the wash water 372is provided within an external washing loop.

FIG. 4 shows an embodiment of a suspended solids separation system 400in which clarified free bio-oil 413 is recovered via conventional meansfrom clarified concentrated thin stillage 405, such as with any suitabletype of centrifuge 412, i.e., without a bio-oil recovery system (250) asshown in FIG. 2. In one embodiment, the centrifuge 412 is any type oftricanter or decanter. As discussed herein, in addition to producing theclarified free bio-oil 413, the other streams exiting the centrifuge 412include solids 415 and a de-oiled clarified concentrated thin stillage414, which can be provided to the evaporator 204, to a molasses product406 and/or to the molasses product tank 218.

As such, in the embodiment shown in FIG. 4, the suspended solidsseparating system 400 do not include a bio-oil recovery system (250) asshown in FIG. 2. Otherwise, the process can begin, in one embodiment, byseparating whole stillage 124 from any suitable source, such as fromethanol production, in a decanter 126 to produce centrate 427 and a wetcake product 428. At start-up, the wet cake product comprisesconventional wet cake, and thereafter, can comprise a molassesproduct-containing wet cake, and, in some embodiments, can additionallyor alternatively include fine suspended solids from a fine suspendedsolids stream (e.g., 529, FIG. 5).

In the embodiment shown in FIG. 4, the wet cake product 428 is providedto a first dryer 219 to produce DDG 420. A portion of the centrate 427is provided as “backset,” a portion or all of which can be provided tothe mechanical processor 240 as shown in FIG. 4. The other portion ofthe centrate 427, although compositionally the same, is referred to inthis point of the process as thin stillage.

The thin stillage product 460 (comprised at start-up of thin stillage(not shown) and, during operation, of thin stillage in combination withclarified thin stillage 442 in varying ratios), can be provided to themechanical processor 240. As with the above described embodiments, thethin stillage product 460 enters the mechanical processor 240 where itis separated into a fine suspended solids stream 429 and clarified thinstillage 442. In contrast to the embodiment shown in FIG. 2, however,the embodiment in FIG. 4 does not include a thin stillage product tank(203), although such a tank can be provided if desired. As such, theclarified thin stillage 442 (now depleted in protein and enriched inbio-oil and soluble as compared to the thin stillage product 460) isprovided directly to the evaporator 204 for dewatering to produceclarified concentrated thin stillage 405.

The clarified concentrated thin stillage 405 is further processed in acentrifuge 412 to produce the clarified free bio-oil 413, solids 415 andde-oiled clarified concentrated thin stillage 414. The de-oiledclarified concentrated thin stillage 414 can, in turn be provided to theevaporator 204, and/or a reduced suspended solids stream, such as themolasses product 406 shown in FIG. 4 and/or a reduced suspended solidsstream tank, such as the molasses product tank 218 shown in FIG. 4.

Other reduced suspended solids streams, such as the molasses product 406shown in FIG. 4, can then be provided to the molasses product tank 218as shown and sold and/or combined with the wet cake product 428 andprovided to the first dryer 219 to produce DDGS 421. Optionally, themolasses product 406 can then be provided to the wet cake product 428and can optionally also be provided as DWGS. Optionally, the molassesproduct 406 can be sold and the wet cake product 428 provided to thefirst dryer 219 to produce DDG 420.

Otherwise, the process proceeds as described in FIG. 2, with the finesuspended solids stream 429 being processed in any suitable manner. Inthe embodiment shown in FIG. 4, the fine suspended solids stream 429 isprovided to a second dryer 244 to produce Dry Distiller's Solubles (DDS)446.

In the embodiment shown in FIG. 5, the suspended solids separatingsystem 500 does not include any type of bio-oil recovery, i.e., norecovery of a bio-oil phase 236, as in FIG. 2 and no recovery ofclarified free bio-oil 413 as in FIG. 4. However, as in otherembodiments, whole stillage 124 can be derived from any suitable source.The system 500 shown in FIG. 5, can begin with, in one embodiment,separating whole stillage 124 in a decanter 126 to produce centrate 527and a wet cake product 528, which, at start-up comprises conventionalwet cake, and thereafter, can comprise a molasses product-containing wetcake, and, as shown in FIG. 5, can additionally or alternatively includefine suspended solids from a fine suspended solids stream 529.

In the embodiment shown in FIG. 5, the wet cake product 528 is providedto a dryer 119 to produce DDG 520. A portion of the centrate 527 isprovided as “backset,” a portion or all of which can be provided to themechanical processor 240 as shown in FIG. 5. The other portion of thecentrate 527, although compositionally the same, is referred to in thispoint of the process as thin stillage.

The thin stillage product 560 (comprised at start-up of thin stillage(not shown) and, during operation, of thin stillage in combination withclarified thin stillage 542 in varying ratios), can be provided to themechanical processor 240 where it is separated into a fine suspendedsolids stream 529 and clarified thin stillage 542.

As with the embodiment shown in FIG. 4, the embodiment in FIG. 5 doesnot include a thin stillage product tank (203), although such a tank canbe provided if desired. As such, the clarified thin stillage 542 (nowdepleted in protein and enriched in bio-oil and soluble as compared tothe thin stillage product 560) is provided directly to the evaporator204 for dewatering to produce a reduced suspended solids stream, such asthe molasses product 506 shown in FIG. 5.

In contrast to the embodiments shown in FIGS. 2 and 4, however, in theembodiment shown in FIG. 5, the fine suspended solids stream 529 is notdried, but, as noted above, is instead provided to the decanter 126where it can be processed and/or dried as described above. When the finesuspended solids stream 529 is provided to the decanter 126, it can becombined with the wet cake product 528 where it can be dried in a dryer119, such as a distiller's rotary grain dryer, thus increasing thevolume and protein content of the resulting DDG 520.

The various reduced suspended solids streams produced in the evaporator204, such as the molasses product 506 shown in FIG. 5, can be providedto a molasses product tank 218 and sold and/or combined with the wetcake product 528 and provided to the dryer 119 to produce DDGS 521.Optionally, the wet cake product 528 containing varying amounts of thefine suspended solids stream 529 can additionally or alternatively alsobe provided as DWG.

The various embodiments described herein further produce a de-oiledwater phase, which can be further concentrated to lower moisturecontents (i.e., down to about 20% moisture content on a dry weightbasis, while remaining a pumpable liquid. This is due to the presence ofcomponents, such as glycerol, lactic acid, and acetic acid present inliquid form and thus able to dissolve residual sugars present in thede-oiled liquid phase.

The specific materials and designs of additional minor componentsnecessary to perform the process, e.g., valves, pumps, lines, and thelike, are understood in the art and are not all described in detailherein. The apparatus and method can further be implemented using avariety of specific equipment available to and understood by thoseskilled in process control art. For example, means for sensingtemperature, pressure and flow rates in all of the flow lines may beaccomplished by any suitable means. It will also be appreciated by thoseskilled in the art that the various embodiments can include a systemcontroller.

Specifically, the system controller can be coupled to various sensingdevices to monitor certain variables or physical phenomena, process thevariables, and output control signals to control devices to takenecessary actions when the variable levels exceed or drop below selectedor predetermined values. Such amounts are dependent on other variables,and may be varied as desired by using the input device of thecontroller. Such sensing devices may include, but are not limited to,devices for sensing temperatures, pressures, density and flow rates, andtransducing the same into proportional electrical signals fortransmission to readout or control devices may be provided for in all ofthe principal fluid flow lines. Such a controller may be a local orremote receiver only, or a computer, such as a laptop or personalcomputer as is well-known in the art. In one embodiment, the controlleris a personal computer having all necessary components for processinginput signals and generating appropriate output signals as is understoodin the art. These components can include a processor, a utility, adriver, an event queue, an application, and so forth, although theembodiments are not so limited. In one embodiment, the controller has anon-volatile memory comprised of a disk drive or read only memory devicethat stores a program to implement the above control and storeappropriate values for comparison with the process variables as is wellknown in the art. In other embodiments, the information is storedremotely.

In one embodiment, these components are all computer programs executedby a processor of the computer, which operates under the control ofcomputer instructions, typically stored in a computer-readable mediasuch as a memory. In this way, useful operations on data and other inputsignals can be provided by the computer's processor. The controller alsodesirably includes an operating system for running the computerprograms, as can be appreciated by those within the art. The systemcontroller may also comprise a machine coupled to a control panel.Buttons and dials can be provided on the control panel to allowmodification of the values and to control the agricultural biofuelenergy generating system to take the desired steps described herein.

The system controller can also be programmed to ignore data from thevarious sensors when the operator activates certain other buttons anddials on the control panel as he deems necessary, such as fill overrideor emergency stop buttons. Alternatively, or in addition to theforegoing, the control panel can include indicator lights or digitaldisplays to signal an operator as to the status of the operation.Indicator lights can also be used to signal that a certain variablelevel is outside the desired range, therefore alerting the operator tothe need for corrective action. In such an embodiment, the correctiveaction is not automatic, but requires the operator to initiatecorrective action by either pushing a specific button or turning aspecific dial on the control panel, or by manually adjusting theappropriate valve or device.

Additionally, as is known in the art, in implementing the systemdescribed herein, general chemical engineering principles are adheredto, including accounting for the various types of energy and materialsbeing input to and output from the system, in order to properly size thesystem. This includes not only the energy associated with mass flow, butalso energy transferred by heat and work. In some embodiments, thesystem is optimized for maximum performance utilizing any knownoptimization methods known in the art. The present subject matter isfurther described by reference to the following examples, which areoffered to further illustrate various embodiments. It should beunderstood, however, that many variations and modifications may be madewhile remaining within the scope of the embodiments described herein.

Example 1

Thin stillage starting material (e.g., 202, FIG. 2) was obtained from acommercial corn-to-ethanol production facility (hereinafter “ethanolproduction facility”) and analyzed for content. The thin stillage 202was thereafter further processed and analyzed as described below.

Thin Stillage Content

Thin stillage total % solids and thin stillage dissolved % solids weredetermined using a calibrated Mettler Toledo analytical balance and aBinder forced draft laboratory oven set at a temperature ofapproximately 105° C. The procedure involved calibrating the analyticalbalance and validating with standardized weights.

Determination of thin stillage total % solids and dissolved solids,included taking the fresh, hot sample and putting immediately into ahermitically sealed bottle to allow cooling of each sample for about 45minutes to minimize moisture loss while the sample was being handled.For the dissolved % solids, samples were centrifuged at a maximumrevolutions per minute (RPM) for approximately 10 minutes in alaboratory style centrifuge. Using the calibrated analytic balance, theinitial weight of the aluminum weigh pan was recorded and the balancetared with the weigh pan.

For total % solids determination, approximately 10 to approximately 12grams (g) of the cooled sample were added. For dissolved % solidsdetermination, the sample was thereafter pipetted into a syringe with a0.2 micrometer (μm) High Pressure Liquid Chromatography (HPLC) syringefilter. Thereafter, about 10 to about 12 grams (g) of the sample wereadded to the drying pan by passing the liquid through the filter,thereby removing suspended solids from the material, the total gramswere recorded.

For both types of solids, the samples were heated for about 3 hours to atemperature of approximately 105° C. in a forced draft drying oven. Mostsamples were then placed in a desiccator to further cool undercontrolled conditions. However, samples, which were weighed within about5 minutes of being removed from the oven, were not placed in thedesiccator, but were instead allowed to cool for about 1 to about 2 minprior to weighing. The final dry weight of the dried sample and weighpan were then recorded.

The various % solids were calculated as follows:

Total % Solids=((Final Weight−Initial Pan Weight)/Grams of Sample)×100

% Dissolved Solids=((Final Weight−Initial Pan Weight)/Grams ofSample)×100

% Suspended Solids=Total % Solids−Dissolved % Solids

% Suspended Ratio=% Suspended Solid % Total Solids

% Dissolved Ratio=Dissolved Solids % Total Solids

% Suspended to % Dissolved Ratio=% Suspended Solids % Dissolved Solids

Compositional analysis of the thin stillage was performed using aShimadzu HPLC system configured with SIL-20AC HT refrigeratedautosampler, LC-20AT pump, CTO-20A oven, and RID-10A detector. Themethod used was Phenomenex Rezex ROA Organic Acid H+150×7.8 mm columnwith 0.6 mL/min flow rate, temperature in autosampler at about 4° C.,and at about 65° C. column temperature. The results are shown in Table1, which also includes the Degree of Polymerization (DP) for dextrinmolecules.

TABLE 1 Soluble composition of thin stillage as analyzed by HPLCweight/volume % Lactic Acetic DP4+ DP3 Maltose Glucose Acid GlycerolAcid Ethanol average 0.62 0.07 0.57 0.17 0.12 1.64 0.07 0.01 stdeva 0.190.02 0.21 0.08 0.04 0.53 0.03 0.01 max 1.18 0.08 0.73 0.31 0.15 2.08 0.10.03 min 0.27 0 0.08 0.04 0.02 0.32 0.01 0 # samples 53 53 53 53 53 5353 53 DP4+ (Dextrin and 4 or more additional sugars) DP3 (Dextrin plus 3additional sugars)

The resulting % solids contents calculated as described above, are shownin Table 2.

TABLE 2 Compositional analysis of thin stillage pH % TS % Soluble % TSS% Fat DMB average 4.02 4.14 2.90 1.25 19.63 stdeva 0.15 0.67 0.33 0.414.35 max 4.25 5.69 4.10 3.00 26.18 min 3.64 3.26 2.15 0.02 9.53 #samples 53 53 53 53 53 % Total Solids (TS) = weight/weight percentage ofsample which is not water % soluble = weight/weight percentage of whichis soluble in water % Total Suspended Solids (TSS) = weight/weightpercentage of sample which is notsoluble in water % Fat Dry Matter Basis(DMB) = weight percentage of a sample that is soluble in petroleumether/weight percentage of sample which is not water

Processing and Analysis of Thin Stillage

Analysis of the process streams was performed according to the methodsdescribed herein and/or known to those skilled in the art using aShimadzu HPLC system configured with SIL-20AC HT refrigeratedautosampler, LC-20AT pump, CTO-20A oven, and RID-10A detector. Themethod used was Phenomenex Rezex ROA Organic Acid H+150×7.8 mm columnwith 0.6 mL/min flow rate, temperature in autosampler 4° C., and a 65°C. column temperature.

After the initial compositional determinations were made, as describedabove, the thin stillage was provided to a shot style disc stackcentrifuge Flottweg® model AC1000. The temperature of the thin stillagefeed to the centrifuge was kept at a constant 180° F. (82° C.) duringall centrifugation testing. The underflow (i.e., fine suspended solidsstream, i.e., 229, FIG. 2) from the centrifuge was transferred to aholding tank where the elevated temperature was maintained. Overflow(i.e., clarified thin stillage, i.e., 242, FIG. 2) was collected forcompositional analysis and dryer testing using an Anhydro spray dryer.The dried product retained color and appeared suitable for furtherprocessing. Samples of the overflow and underflow were simultaneouslytaken every two to four hours during the processing and individuallyanalyzed to determine the split and efficiency of the system. Thefraction of suspended solids captured by the centrifuge averaged 93.6%as shown in Table 3.

TABLE 3 Volumetric ratios of suspended solids versus total volume inspin test feed overflow underflow suspended “shot suspended suspendedsuspended solids cycle” volume volume volume recovery seconds ratioratio ratio ratio Average 80 0.082 0.005 0.794 0.936 Std dev 0 0.0140.003 0.115 0.044 Max 80 0.107 0.018 0.971 0.967 Min 80 0.036 0.0040.286 0.75 # samples 48 40 40 40 40 (A “shot cycle” refers to theopening and closing of the gate or door against which solids build upwhen closed and are released when open).

FIGS. 6 and 7 are images of spin vials showing suspended captureefficiency from the AC1000. FIG. 6 comprises a set of four spin vials602, 604, 606 and 608. Spin vial 602 is empty but is included to showthe volume delineations. Black lines drawn on spin vials 604, 606 and608 are labeled as 610, 612 and 614, respectively. These markings denotean intersection line between the suspended solids and supernatantlayers. Spin vial 608 is a sample containing the feed material withapproximately 1.5 mL solids in a 14 mL sample. Spin vials 604 and 606are overflow samples produced from the starting material in spin vial608 according to the process described above with the high speedcentrifuge. As FIG. 6 shows, spin vials 604 and 606 each haveapproximately 0.08 mL of solids in a 14 mL sample. This represents 94.7%suspended solids capture efficiency.

The feed rate was adjusted during the operation starting at about 2gallons per minute and ramping to about 4 gallons per minute over a 4day test period. A second 5 day test period used an approximately 4.4gallon per minute feed rate was conducted at a later time. Compositionalanalysis of the overflow and underflow obtained in the manner describedabove during the 9 days of operation is shown in Tables 4 and 5.

TABLE 4 Compositional analysis of 53 overflow samples taken over the 9days of centrifuge operation Centrifuge Overflow % % Fat % TS Soluble %TSS DMB Avg 3.5 3.45 0.30 20.28 Stdeva 0.44 0.49 1.80 6.05 Max 5.80 5.8012.85 38.51 Min 2.93 2.74 −0.57 7.4 # samples 53 51 53 53

TABLE 5 Compositional analysis of 53 overflow samples taken over 9 daysof centrifuge operation Centrifuge Underflow % Fat % Prot % TS % Soluble% TSS DMB DMB Avg 13.86 1.33 12.64 7.55 40.57 Stdeva 2.31 0.71 2.64 2.973.34 Max 20.21 4.28 21.08 15.27 49.01 Min 8.39 0.22 6.46 2.47 31.19 #samples 53 46 53 53 53 % Prot DMB = (weight percentage of Nitrogen of asample X 6.25)/weight percent of a sample which is not water

A mass balance split between the two fractions was calculated by usingthe ratios of suspended-to-dissolved solids in feed and comparing to theoverflow and underflow. This analysis showed that about 70% of thenon-water mass splits into the overflow and about 30% splits into theunderflow. Multiplying this mass split times the fraction of bio-oil ineach material (20.3% concentration fat in overflow and 7.6%concentration fat in underflow), it was determined that approximately86% of the bio-oil in the thin stillage product was captured in theoverflow and 14% of the bio-oil was captured in the underflow.

Overflow from the centrifuge separation was concentrated under vacuum atapproximately 200° F. (93° C.) from an initial Brix concentration of 5.3to a final Brix concentration of 39.1 degrees Brix (hereinafter “Brix”).(“Degrees Brix” refers to sugar content of an aqueous solution. Onedegree Brix corresponds to 1 gram of sucrose in 100 grams of solution,thus representing the strength of the solution as a percentage by weight(% w/w)). Concentrated material was drawn out of the evaporator as theBrix approached 35 in order to build a stock of 35 Brix to test forbio-oil extraction via centrifugation. Brix measurements were made witha handheld Brix refractometer during the concentration process. As Brixmeasurements were made, the samples were also tested for bio-oil vialaboratory spin testing. There was a fair amount of emulsion in thebio-oil layer. As the total solids concentration increased, thebio-oil/emulsion concentration increased, as observed by the spintesting (which determined solids by volume).

See, for example FIG. 8 which shows a volume/volume emulsion/bio-oilwith increasing Brix concentration. As can be seen, the samplesexhibited increasing bio-oil emulsion as the amount of solids increased.

The 35 Brix concentrate was centrifuged with a Flottweg™ Z23 tricanterfor bio-oil recovery. The feed was delivered hot to the tricanter and anemulsified bio-oil layer was recovered from the centrifuge. Thisemulsified bio-oil was broken into free bio-oil and water phases byadding ethanol at elevated temperature to the emulsion and then flashingthe ethanol back out of the emulsified mixture. (See patent '627). Usingthis technique, it was observed that recoveries over 80% of theoreticalare achievable.

Example 2

In this testing, the thin stillage from the same commercial source asdescribed in Example 1 was subjected to further processing andcompositional data on overflow (i.e., fine suspended solids stream,i.e., 229, FIG. 2) and underflow (i.e., clarified thin stillage, i.e.,242, FIG. 2) was obtained.

A 600 gallon tank and tube-and-shell heat exchanger (constructedin-house) were used as an evaporator in the pilot plant. A FlottwegAC1000 (disc stack) was used to remove suspended solids from the thinstillage. The AC1000 was operated at a rate of about 2 to 4 gpm. Theevaporative rate on the evaporator was about 1.1 gpm. A Flottweg Z23(tricanter) was also used to separate the emulsion concentrate. Amodified commercial spray dryer was used to spray dry the centrifugedsolids.

Suspended solids recovery was about 95%, while DDS recovery was betweenabout 55 up to 80 v/v % concentration. Protein levels in the DDS weremeasured at about 40%, with bio-oil content about 5%.

Table 6 shows compositional data from this testing determined accordingto the methods described in Example 1 and other methods known to thoseskilled in the art:

TABLE 6 Compositional Data (% of dry matter) Centrifuge Feed OverflowUnderflow Total Total Total pH Fat solids Fat solids Protein Fat solidsavg 4.0 20 4.3 21. 3.7 42 5.3 14 std 0.36 2.5 0.37 3.1 0.50 3.1 1.9 1.9max 4.3 24. 5.7 27 5.8 49 9.4 18 min 3.6 14 3.8 16 3.1 34 2.5 12

The fine suspended solids stream (i.e., 229 in FIG. 2) had thecomposition as shown in Table 7:

TABLE 7 Fine Suspended Solids Stream Analysis (% of dry matter unlessnoted otherwise) Dry Basis As Received Moisture  5.15% Dry Matter 94.85%Protein, Crude 29.39 27.88% Acid Detergent Insoluble Protein 0.62  0.59%Neutral Detergent Insoluble Protein 2.12  2.01% Soluble Protein (% ofCrude Protein)   18% ADF-Acid Detergent Fiber 1.35  1.28% NDF-NeutralDetergent Fiber 5.13  4.87% NFC- Non Fibrous Carbohydrates 38.46    %Lignin-Acid Insoluble Less than 0.2    % NEL: Net Energy-Lactation 1.331.26 Mcal/lb NEG: Net Energy-Gain 1.06 1.01 Mcal/lb NEM: NetEnergy-Maintenance 1.46 1.38 Mcal/lb TDN: Total Digestible Nutrients124.90 118.47%  Digestible Energy - DE 2.50 2.37 Mcal/lb MetabolizableEnergy - ME 2.05 1.95 Mcal/lb Fat (EE) 23.96 22.73% Ash 5.18  4.91%Calcium 0.14  0.13% Phosphorus 0.89  0.84% Potassium 1.11  1.05%Magnesium 0.34  0.32% Sodium 0.49  0.46% Chloride 0.08  0.08% Sulfur1.28  1.21% Cobalt Less than 0.2      ppm Copper 17.30  16.41 ppm Iron258.00 244.71 ppm Manganese 46.20  43.82 ppm Molybdenum Less than 0.3     ppm Zinc 53.70  50.93 ppm Total Starch 12.3  11.7% RFV-RelativeFeed Value 1593 s.u.

The molasses product (e.g., 206) had a composition in a first test asshown in Table 8:

TABLE 8 Molasses Product Analysis (Run 1) (% of dry matter unless notedotherwise) Dry Basis As Received Moisture, Karl-Fischer  36.2% DryMatter  63.8% Protein, Crude 14.091  8.99% Acid Detergent InsolubleProtein    0% Neutral Detergent Insoluble Protein    0% Soluble Protein(% of Crude Protein)    98% ADF-Acid Detergent Fiber 1.254   0.8%NDF-Neutral Detergent Fiber 1.881   1.2% NFC- Non Fibrous Carbohydrates60.94  38.88% Lignin-Acid Insoluble 0 NEL: Net Energy-Lactation 0.910.581 Mcal/lb NEG: Net Energy-Gain 0.67 0.427 Mcal/lb NEM: NetEnergy-Maintenance 0.98 0.625 Mcal/lb TDN: Total Digestible Nutrients87.13 55.589% Digestible Energy - DE 1.746 1.114 Mcal/lb MetabolizableEnergy - ME 1.432 0.914 Mcal/lb Fat By Acid-Hydrolysis 7.853  5.01% Ash15.251  9.73% Calcium 0.094  0.06% Phosphorus 2.006  1.28% Potassium 2.9 1.85% Magnesium 0.956  0.61% Sodium 1.254   0.8% Chloride 0.627   0.4%Sulfur 2.006  1.28% Cobalt   0 ppm Copper 4.561 2.91 ppm Iron 133.07284.9 ppm Manganese 102.351 65.3 ppm Molybdenum   0 ppm Zinc 115.831 73.9ppm Total Starch 5.799   3.7%The HPLC profile (% w/v) for the molasses product of Table 8 is shown inTable 9.

TABLE 9 DMB - HPLC profile (% W/V) Molasses Product DP4+ DP3 MaltoseGlucose Lactic Glycerol Acetic Ethanol 1 12.64 1.71 8.09 3.33 2.66 36.520.27 0.00

The molasses product (e.g., 206) had a composition in a second test asshown in Table 10:

TABLE 10 Molasses Product Analysis (Run 2) (% of dry matter unless notedotherwise) Dry Basis As Received Moisture, Karl-Fischer  17.3% DryMatter  82.7% Protein, Crude 8.767  7.25% Acid Detergent InsolubleProtein    0% Neutral Detergent Insoluble Protein    0% Soluble Protein(% of Crude Protein)   100% ADF-Acid Detergent Fiber 0.931  0.77%NDF-Neutral Detergent Fiber 1.282  1.06% NFC- Non Fibrous Carbohydrates67.13 55.517% Lignin-Acid Insoluble    0% Fat By Acid-Hydrolysis 12.201 10.09% Ash 10.629  8.79% Calcium 0.085  0.07% Phosphorus 1.79  1.48%Potassium 2.963  2.45% Magnesium 0.762  0.63% Sodium 0.568  0.47%Chloride 1.112  0.92% Sulfur 0.653  0.54% Cobalt   0 ppm Copper 3.4582.86 ppm Iron 73.156 60.5 ppm Manganese 23.216 19.2 ppm Molybdenum   0ppm Zinc 73.156 60.5 ppm Total Starch 2.539   2.1%The HPLC profile (% w/v) for the molasses product of Table 10 is shownin Table 11.

TABLE 11 DMB - HPLC profile (% W/V) Syrup DP4+ DP3 Maltose GlucoseLactic Glycerol Acetic Ethanol 2 10.84 1.38 6.57 6.62 2.74 36.02 0.260.00

See also FIG. 9 showing spin vials containing the molasses productobtained in this testing at 30%, 40% and 50% total solids, whichcontains varying amounts of emulsion concentrate.

It was observed that overflow held for more than 14 days allowedMaillard products to form, which likely resulted in a lower qualitymolasses product. Possible solutions to this issue are discussed inExample 4 (Prophetic).

Additionally, the Regenerative Thermal Oxidizer (RTO) did not functionproperly during the evaporation run, causing loss of the vacuum source.As a result, the temperature of the molasses product in the evaporatorincreased from 170° F. to 215° F., thus overcooking the molassesproduct, causing an off-odor in the molasses product and producingadditional Maillard reaction products. Possible solutions to this issueare discussed in Example 5 (Prophetic).

Example 3

Centrate (e.g., 227, FIG. 2) from a decanter (e.g., 126, FIG. 2) wastaken from the same. Commercial ethanol production facility described inExample 1 during real-time operations.

An FQ950 (Fluid Quip) stack nozzle centrifuge (size 40 nozzle) was usedto recover suspended solids (comprising primarily fine suspended solidsas defined herein) from the centrate. Samples were drawn off directlyfrom the centrate into the centrifuge at a temperature of approximately180° F. (82° C.).

The centrifuge was flushed twice per day during testing. In-placecleaning was performed every 7 days using 5% caustic soda concentration.

The centrifuge was operated at a full-rated rotation rate. Feed rate tothe centrifuge is shown below in Table 12. Overflow from the centrifugewas transferred back into the evaporation system in the facility.Underflow from the centrifuge was transferred to the decanter system inthe facility. The fraction of suspended solids captured by thecentrifuge averaged 86.3% as shown in Table 13.

Overflow and underflow rates are also shown in Table 12. The centrifugetended to entrain air into the overflow and underflow process streams,which likely introduced a minor error (less than 15%) in the flow ratemeter readings for these streams. As such, the values given in Table 12are approximate

TABLE 12 Volumetric ratios of suspended solids versus total volumein-spin test feed overflow underflow suspended suspended suspendedsuspended solids feed rate overflow underflow volume volume volumerecovery (Lpm) (Lpm) (Lpm) ratio ratio ratio ratio Average 1500 1150 4250.13 0.02 0.3 0.9 st. dev. 120 200 140 0.02 0.01 0.05 0.1 Max 1800 1830540 0.2 0.07 0.47 1 Min 1025 800 0 0.07 0 0.17 0.4 # samples 165 165 165165 165 165 165

Example 4 Prophetic

Improved results as compared to those discussed in Example 2 may beobtained by matching evaporator performance rate with overflowproduction rate. In this way, overflow material at 190° F. (88° C.) iskept for a number of hours versus weeks before going to the evaporator.

Improved results may additionally or alternatively be obtained by usingan additional heat exchanger may be used to increase heat input into theevaporator to increase the throughput of the system. The new heatexchanger may be put in parallel with the existing heat exchanger toincrease the evaporative rate by approximately 2.5 times. This isexpected to create a 2.5 gpm (9.5 Lpm) condensate production rate.

Improved results may additionally or alternatively be obtained by usingan additional vacuum line to reduce pressure in the evaporator, thuskeeping the temperature down and/or increasing the flux rate through theexchanger.

These processing steps may be tested alone or in combination, withimproved results possible, as compared to the results in Example 2.

Example 5 Prophetic

Improved results as compared to those discussed in Example 2 may beobtained by monitoring evaporator temperatures.

Improved results may additionally or alternatively be obtained byselecting 35 Brix as a target concentration for the molasses productprior to bio-oil recovery. Products above this concentration can bede-oiled with Z23.

Improved results may additionally or alternatively be obtained byselecting 70-75 Brix as a target concentration for the final molassesproduct concentration based on flowability. This concentration can beaccomplished through evaporation.

These processing steps may be tested alone or in combination, withimproved results possible, as compared to the results in Example 2.

Example 6 Prophetic

DDS material has a high variability in fat content, likely due to theshot cycle frequency being used on the unit combined with feed rate. Theworking hypothesis is that after centrifugation, the DDS material has afull open shot cycle, with the next cycle having very low bio-oilcontent because the system is getting maximum recovery. Each successiveshot cycle will produce a higher bio-oil content because the system isgetting maximum recovery. Each successive shot cycle will produce ahigher bio-oil content DDS recovery. It is desired to have low bio-oilcontent in the DDS material, as well as a consistent product so thebio-oil concentration will be determined with an increased degree ofaccuracy.

The shot cycle hypothesis will be tested by taking a series of samplesthroughout the full cycle to determine the compositional make-up of thebio-oil. Depending on the results, the shot cycle will be altered inorder to produce DDS material that contains no more than 5% fat.

In one embodiment, a method is provided, comprising clarifying a thinstillage product in a mechanical processor (e.g., centrifuge and/or oneor more filters, and the like) to produce a fine suspended solids streamand clarified thin stillage; and providing the thin stillage product andthe clarified thin stillage, separately or in a combined stream, to oneor more evaporators to produce one or more reduced suspended solidsstreams, each stream having a reduced amount of suspended solids and alower viscosity as compared to process streams having a comparable totalsolids content and which contains a higher amount of suspended solids.The suspended solids can comprise, in one embodiment, less than about10% by weight of the total solids content and the total solids contentcan be between about 68% and about 72% by weight. In one embodiment,substantially all or a majority of the clarified thin stillage can beprovided to the thin stillage product.

In one embodiment, at least one of the one or more reduced suspendedsolids stream has a total solids content comprising suspended solids anddissolved solids in an amount between about 30% and about 90% by weight,wherein the suspended solids comprise less than 25% by weight of thetotal solids content.

At least one of the one or more reduced suspended solids stream can be,for example, clarified concentrated thin stillage, which contains anamount of bio-oil that is greater, by volume, than an amount of bio-oilpresent in a concentrated thin stillage that has not been clarified. Insome embodiments, the clarified concentrated thin stillage can besubject to mechanical processing to produce a bio-oil product, such as abio-oil phase or free bio-oil.

In one embodiment, the mechanical processing produces an emulsionconcentrate that is broken in an emulsion breaking reaction to producethe bio-oil phase. In one embodiment, the mechanical processing alsoproduces a solids stream and a de-oiled clarified concentrated thinstillage product, and the method further comprises providing thede-oiled clarified concentrated thin stillage product to the one or moreevaporators.

In one embodiment, at least one of the one or more reduced suspendedsolids stream is a molasses product having a total solids content noless than about 45% by weight, wherein the suspended solids compriseless than 25% by weight down to about 0% of the total solids content.

The method can further comprise, for example, combining at least aportion of the one or more reduced suspended solids streams with wetcake to produce a wet cake product containing reduced suspended solids,and drying the wet cake product to produce a distillers dried grain.

In one embodiment, the method further comprises providing at least aportion of the one or more reduced suspended solids streams to a dryerto produce distiller's dried grain solubles and/or drying the finesuspended solids stream to produce dry distiller's solubles containingsingle cell proteins.

In one embodiment, the thin stillage product may be produced from lowwater extractable non-starch polysaccharide (NSP)-containing plantbiomass. Use of NSP-containing biomass provides reduced protein dilutionin the resulting process stream. As such, an improved feed product fromthe underflow (e.g., fine suspended solids stream, e.g., 229, FIG. 2)may be provided.

Various bio-products can be produced according to the methods describedherein, including, but not limited to, clarified concentrated thinstillage, clarified thin stillage, fine suspended solids stream, amolasses product, dry distiller's solubles, wet cake product,distiller's dry grain, distiller's dry grain solubles, and combinationsthereof.

In one embodiment, a method is provided comprising clarifying a thinstillage product in a mechanical processor to produce a fine suspendedsolids stream and clarified thin stillage; providing the thin stillageproduct and the clarified thin stillage, separately or in a combinedstream, to one or more evaporators to produce at least two reducedsuspended solids streams, each of the at least two streams having areduced amount of suspended solids and a lower viscosity as compared toprocess streams having a comparable total solids content but containinga higher amount of suspended solids; and subjecting at least one of theat least two reduced suspended solids streams to mechanical processingto produce a bio-oil product. The at least two reduced suspended solidsstreams may comprise, for example, a stream containing clarifiedconcentrated thin stillage and a stream containing a molasses product,wherein the clarified concentrated thin stillage is subjected to themechanical processing. The molasses product may contain, for example,two to three times the amount of bio-oil per volume as compared toconcentrated thin stillage. In one embodiment, the molasses product hasbetween about 65% and 75% total solids, by weight, and contains betweenabout 8% and about 12% bio-oil, by volume. The molasses product may besold, combined with wet cake, and/or dried.

In one embodiment, a method is provided, comprising clarifying a thinstillage product to produce one or more reduced suspended solidsstreams, each having a total solids content between about 30% and about90% by weight, wherein the total solids content comprises suspendedsolids and dissolved solids, and the suspended solids comprise less than25% by weight of the total solids content. In one embodiment, a systemis provided, comprising a clarifier for clarifying a thin stillageproduct to produce a fine suspended solids stream and clarified thinstillage; and one or more evaporators for evaporating the thin stillageproduct and the clarified thin stillage to produce one or more reducedsuspended solids streams, each having a reduced amount of suspendedsolids and a lower viscosity as compared to a process stream having acomparable total solids content but containing a higher amount ofsuspended solids. A system control device (e.g., a holding tank that isoptionally connected to a heat source) that is adapted to provide aquantity of thin stillage product for use downstream may also be used.

In one embodiment, the system further comprises a biomass processingfacility having one or more process streams and configured to produce abiofuel and a bio-oil-containing process stream, wherein the biomassprocessing facility includes a dewatering system for dewatering thebio-oil containing process stream to produce an emulsion concentratecontaining entrapped bio-oil; and an emulsion breaking system configuredto at least partially break the emulsion concentrate with an emulsionbreaking additive so that the entrapped bio-oil (e.g., corn oil) isreleased. The system can further comprise, for example, a bio-productproduction facility capable of producing bio-products, such as biofuels,biochemical, and the like. In one embodiment, the biofuel is alcohol(e.g., ethanol, butanol, etc.).

In one embodiment, a method for reducing a dryer load in a bio-productproduction facility is provided comprising clarifying a thin stillageproduct in a mechanical processor to produce a fine suspended solidsstream and clarified thin stillage; and providing the thin stillageproduct and the clarified thin stillage, separately or in a combinedstream, to one or more evaporators to produce one or more reducedsuspended solids streams, each stream having a reduced amount ofsuspended solids and a lower viscosity as compared to process streamshaving a comparable total solids content and which contains a higheramount of suspended solids, wherein the dryer load is reduced ascompared to a method performed without a clarifying step.

In one embodiment, a method for improving bio-product production yieldis provided comprising clarifying a thin stillage product in amechanical processor to produce a fine suspended solids stream andclarified thin stillage; and providing the thin stillage product and theclarified thin stillage, separately or in a combined stream, to one ormore evaporators to produce one or more reduced suspended solidsstreams, each stream having a reduced amount of suspended solids and alower viscosity as compared to process streams having a comparable totalsolids content and which contains a higher amount of suspended solids,wherein bio-products production yield is increase as compared to amethod performed without a clarifying step.

In one embodiment, a method of reducing emissions in a bio-productproduction facility comprising clarifying a thin stillage product in amechanical processor to produce a fine suspended solids stream andclarified thin stillage; and providing the thin stillage product and theclarified thin stillage, separately or in a combined stream, to one ormore evaporators to produce one or more reduced suspended solidsstreams, each stream having a reduced amount of suspended solids and alower viscosity as compared to process streams having a comparable totalsolids content and which contains a higher amount of suspended solids,wherein emissions from the bio-product production facility are reducedas compared to a method performed without a clarifying step.

In one embodiment, energy costs in the alcohol production facility arereduced as compared with conventional methods, since more moisture canbe removed with evaporators rather than expensive dryers. In oneembodiment, the reduced dryer load allows for an increased rate ofproduction of alcohol and co-products at the alcohol productionfacility. In one embodiment, dryer load is reduced by at least 10%.

In one embodiment, production rate is also improved by operating one ormore evaporators (e.g., first effect evaporators) at a highertemperature, thus reducing the energy required for evaporation. In oneembodiment, the energy requirements for evaporation are reduced by atleast 33%.

DDGS produced according to the embodiments described herein not onlymeets current minimum market levels of 8% bio-oil content by volume, butin some embodiments contain an increased amount of protein, as well as areduced sulfur and ash content.

The various embodiments also reduce production facility emissionsoverall, including emission of volatile organic contaminants (VOCs)since dryer loads are reduced.

Although specific embodiments have been illustrated and describedherein, it will be appreciated by those of ordinary skill in the artthat any procedure that is calculated to achieve the same purpose may besubstituted for the specific embodiments shown. This application isintended to cover any adaptations or variations of the present subjectmatter. Therefore, it is manifestly intended that embodiments of thisinvention be limited only by the claims and the equivalents thereof.

What is claimed is:
 1. A method comprising: clarifying a thin stillageproduct in a mechanical processor to produce a fine suspended solidsstream and clarified thin stillage; and providing the thin stillageproduct and the clarified thin stillage, separately or in a combinedstream, to one or more evaporators to produce one or more reducedsuspended solids streams, each stream having a reduced amount ofsuspended solids and a lower viscosity as compared to process streamshaving a comparable total solids content and which contains a higheramount of suspended solids.
 2. The method of claim 1, wherein thesuspended solids comprise less than about 10% by weight of the totalsolids content and the total solids content is between about 68% andabout 72% by weight.
 3. The method of claim 1, wherein at least one ofthe one or more reduced suspended solids stream has a total solidscontent comprising suspended solids and dissolved solids in an amountbetween about 30% and about 90% by weight, wherein the suspended solidscomprise less than 25% by weight of the total solids content.
 4. Themethod of claim 1, wherein at least one of the one or more reducedsuspended solids stream is clarified concentrated thin stillage, whichcontains an amount of bio-oil which is greater, by volume, than anamount of bio-oil present in a concentrated thin stillage which has notbeen clarified.
 5. The method of claim 4, wherein the clarifiedconcentrated thin stillage is subject to mechanical processing toproduce a bio-oil product.
 6. The method of claim 5, wherein themechanical processing produces an emulsion concentrate which is brokenin an emulsion breaking reaction to produce the bio-oil phase.
 7. Themethod of claim 5, wherein the mechanical processing also produces asolids stream and a de-oiled clarified concentrated thin stillageproduct, and the method further comprises providing the de-oiledclarified concentrated thin stillage product to the one or moreevaporators.
 8. The method of claim 1, wherein at least one of the oneor more reduced suspended solids stream is a molasses product having atotal solids content no less than about 45% by weight, wherein thesuspended solids comprise less than 25% by weight down to 0% of thetotal solids content.
 9. The method of claim 1, wherein substantiallyall of the clarified thin stillage is provided to the thin stillageproduct.
 10. The method of claim 1, further comprising: combining atleast a portion of the one or more reduced suspended solids streams withwet cake to produce a wet cake product containing reduced suspendedsolids; and drying the wet cake product to produce a distillers driedgrain.
 11. The method of claim 1, further comprising: providing at leasta portion of the one or more reduced suspended solids streams to a dryerto produce distiller's dried grain solubles.
 12. The method of claim 1,further comprising drying the fine suspended solids stream to producedry distiller's solubles containing single cell proteins.
 13. The methodof claim 1, wherein the thin stillage product is produced from low waterextractable non-starch polysaccharide-containing plant biomass.
 14. Aproduct made according to the process of claim
 1. 15. The product ofclaim 14, selected from clarified concentrated thin stillage, clarifiedthin stillage, fine suspended solids stream, a molasses product, drydistiller's solubles, wet cake product, distiller's dry grain,distiller's dry grain solubles, and combinations thereof.
 16. A methodcomprising: clarifying a thin stillage product in a mechanical processorto produce a fine suspended solids stream and clarified thin stillage;providing the thin stillage product and the clarified thin stillage,separately or in a combined stream, to one or more evaporators toproduce at least two reduced suspended solids streams, each of the atleast two streams having a reduced amount of suspended solids and alower viscosity as compared to process streams having a comparable totalsolids content but containing a higher amount of suspended solids; andsubjecting at least one of the at least two reduced suspended solidsstreams to mechanical processing to produce a bio-oil product.
 17. Themethod of claim 16, wherein the at least two reduced suspended solidsstreams comprise a stream containing clarified concentrated thinstillage and a stream containing a molasses product, wherein theclarified concentrated thin stillage is subjected to the mechanicalprocessing.
 18. The method of claim 16, wherein the mechanicalprocessing produces an emulsion concentrate which is broken in anemulsion breaking reaction to produce the bio-oil phase.
 19. The methodof claim 17, wherein the molasses product contains two to three timesthe amount of bio-oil per volume as compared to concentrated thinstillage.
 20. The method of claim 17, wherein the molasses product hasbetween about 65% and about 75% total solids, by weight, and containsbetween about 8% and about 12% bio-oil, by volume.
 21. The method ofclaim 17, wherein the molasses product is to be sold, combined with wetcake, and/or dried.
 22. A method comprising: clarifying a thin stillageproduct to produce one or more reduced suspended solids streams, eachhaving a total solids content between about 30% and about 90% by weight,wherein the total solids content comprises suspended solids anddissolved solids, and the suspended solids comprise less than 25% byweight of the total solids content.
 23. The method of claim 22, whereinat least one of the reduced suspended solids product is subject tomechanical processing to produce a bio-oil product.
 24. The method ofclaim 23, wherein the mechanical processing produces an emulsionconcentrate which is broken in an emulsion breaking reaction to producethe bio-oil product.
 25. A system comprising: a clarifier for clarifyinga thin stillage product to produce a fine suspended solids stream andclarified thin stillage; and one or more evaporators for evaporating thethin stillage product and the clarified thin stillage to produce one ormore reduced suspended solids streams, each having a reduced amount ofsuspended solids and a lower viscosity as compared to a process streamhaving a comparable total solids content but containing a higher amountof suspended solids.
 26. The system of claim 25, further comprising asystem control device adapted to provide a quantity of thin stillageproduct for use downstream.
 27. The system of claim 26, wherein thesystem control device is a holding tank which is optionally connectedwith a heat source.
 28. The system of claim 25, further comprising: adewatering system for dewatering a bio-oil containing process stream toproduce an emulsion concentrate containing entrapped bio-oil; and anemulsion breaking system configured to at least partially break theemulsion concentrate with an emulsion breaking additive so that theentrapped bio-oil is released.
 29. The system of claim 28, furthercomprising an alcohol production facility.
 30. The system of claim 29,wherein the alcohol production facility is an ethanol productionfacility.
 31. The system of claim 30, wherein the bio-oil is corn oil.32. A method for reducing a dryer load in a bio-product productionfacility comprising: clarifying a thin stillage product in a mechanicalprocessor to produce a fine suspended solids stream and clarified thinstillage; and providing the thin stillage product and the clarified thinstillage, separately or in a combined stream, to one or more evaporatorsto produce one or more reduced suspended solids streams, each streamhaving a reduced amount of suspended solids and a lower viscosity ascompared to process streams having a comparable total solids content andwhich contains a higher amount of suspended solids, wherein the dryerload is reduced as compared to a method performed without a clarifyingstep.
 33. A method for improving bio-product production yieldcomprising: clarifying a thin stillage product in a mechanical processorto produce a fine suspended solids stream and clarified thin stillage;and providing the thin stillage product and the clarified thin stillage,separately or in a combined stream, to one or more evaporators toproduce one or more reduced suspended solids streams, each stream havinga reduced amount of suspended solids and a lower viscosity as comparedto process streams having a comparable total solids content and whichcontains a higher amount of suspended solids, wherein bio-productproduction yield is increased as compared to a method performed withouta clarifying step.
 34. The method of claim 33 wherein the bio-product isa biofuel or biochemical.
 35. A method of reducing emissions in abio-product production facility comprising: clarifying a thin stillageproduct in a mechanical processor to produce a fine suspended solidsstream and clarified thin stillage; and providing the thin stillageproduct and the clarified thin stillage, separately or in a combinedstream, to one or more evaporators to produce one or more reducedsuspended solids streams, each stream having a reduced amount ofsuspended solids and a lower viscosity as compared to process streamshaving a comparable total solids content and which contains a higheramount of suspended solids, wherein emissions from the bio-productproduction facility are reduced as compared to a method performedwithout a clarifying step.